Sub floating drifting mine



Oct. 19, 1965 L. MICHELSON 3,212,436

SUB FLOATING DRIFTING MINE Filed July 10, 1952 RESERVOIR INVENTORLouisMicbelsmz BY /ma 1%. AQQQA,

ATTORNEYS United States Patent 3,212,436 SUB FLOATING DRIFTING MINELouis Michelson, Middletown, RL, assignor to the United States ofAmerica as represented by the Secretary of the Navy Filed July 10, 1252,Ser. No. 298,214

3 Claims. (Cl. 102-14) (Granted under Title 35, US. Code (1952), sec.266) The invention described herein may be manufactured and used by orfor the Government of the United States of America for governmentalpurposes without the payment of any royalties thereon or therefor.

The present invention relates to subfloating mines and, moreparticularly, to apparatus for maintaining a subfloating mine withinselected limits above and below a predetermined depth of submergencewith a minimum of volume adjusting cycles.

Prior art devices have been found to have short life by reason ofovershooting selected upper and lower depth adjustment limits thusnecessitating long periods of operation of the adjusting mechanism withthe resultant high drain on the battery or other energy storing deviceemployed to furnish power for accomplishing such adjustments.

The device of the present invention employs primarily a volume changingapparatus for maintaining a mine at a substantially constant depth ofsubmergence, there being provided time delay anchor releasing apparatusand apparatus for jettisoning a measured amount of liquid from the minecase when conditions warrant reduction of the weight of the mine.

An object of the present invention is to provide a new and improveddiaphragm control apparatus for a subfloating mine wherein the mine ismaintained at a substantially constant depth.

Another object is to provide a new and improved apparatus forcontrolling the depth of a subfioating mine wherein a novel electrolyticjettisoning device is employed to reduce the weight of the mine.

Still another object is to provide volume adjustment for a subfioatingmine controlled in a novel manner by the pressure of the surroundingwater.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings wherein:

FIG. 1 is a side elevational view of a conventional mine case andshowing the diaphragms and anchor of depth control apparatus of thepresent invention installed therein;

FIG. 2 is a diagram of the mechanical and electrical components of thepresent invention; and

FIG. 3 is a diagram showing the cycles of operation of mechanism.

Referring more particularly to the drawings wherein like numeralsindicate like parts throughout the several views, indicates generally amine case having secured to the lower end 11 thereof by means of bolts12 an anchor 13 of sutficient weight to cause the mine to be negativelybuoyant, the bolts 12 being formed of magnesium or other metals whichwill corrode by electrolysis at a known rate when immersed in sea water.It will thus be seen that anchor or weight 13 is retained on mine 10until bolts 12 are corroded sufficiently to cause the release of theanchor. The mine is retained on the bottom until the anchor is releasedwhereupon the mine, having slightly positive buoyancy, rises in thewater. It will be understood that the size of the bolts is determined sothat the mine will remain on the bottom for the desired length of time.

Mounted in the wall of casing 10 is a flexible diaphragm 14 which is incontact with the sea water when the mine is submerged and which forms awall of the chamber 15. The chamber 15 contains a suitable fluid, suchas light oil 16. A reservoir 17 is mounted wholly within the casing 10and communicates with the chamber 15 through tube 13. A shut-off valve19 is mounted in tube 18 and is turned on or off in accordance with thepressure of the sea water surrounding casing 10, as will be hereinaftermore fully disclosed. A portion of tube 18 is reduced in diameter toform a capillary tube 21 for restricting the flow of fluid 16 betweenchamber 15 and reservoir 17.

Valve 19 is moved to an open position by solenoid 32, which is energizedby a switch indicated generally at 23. Switch 23 comprises a pair ofopposed contacts 24 and 25 which may be adjusted with respect to amovable contact arm 26 disposed therebetween, such adjustment having theeffect of raising or lowering the upper and lower oscillating limits ofthe mine. Movable contact arm 26 is connected to the movable end of aBourdon tube 27 by a link 28, tube 27 being arranged to be activated inaccordance with changes in pressure of the surrounding water such as bythe connection to tube 18. It will thus be seen that when pressure ofthe sea water is exerted on diaphragm 14, pressure is exerted in tube 27tending to straighten the tube in accordance with the amount of pressureexerted. When the pressure reaches a predetermined low value, arm 26engages contact 24. When the pressure reaches a predetermined highvalue, arm 26 engages contact 25.

Contact arm 26 is connected with battery 29, an arming switch 31 beinginterposed therebetween. When arm 26 engages contact 24, arming switch31 being closed, solenoids 32 and 33 are energized. Solenoid 32 movesvalve 19 to the open position, while solenoid 33 moves bridging member34 to bridge contacts 35 and 36 As will be hereinafter more fullydescribed, member 34, when moved to engage contacts 35 and 36, is lockedin engage ment therewith thus maintaining the circuit closed at thispoint after the first energization of solenoid 33 which occurs as themine rises in the water after release of the anchor and the resultantclosing of switch 31. Closing of switch 31 arms the circuit byconnecting battery 29 to contact arm 26, tube 27 moving contact arm 26to engage contact 24 when pressure of the surrounding water is reducedto a predetermined value during the rise of the mine in the water.

When arm 26 engages contact 24 solenoid 32 is energized, opening valve19 and thus permitting fluid 16 to pass from chamber 15 under action ofwater pressure against diaphragm 14. Passage of the fluid is restrictedby the capillary tube 21 prior to the entry thereof into the reservoir17. It will be clear that when valve 19 is opened, diaphragm 14- isforced inwardly by pressure of the water and the volume of mine case 10is reduced sufficiently to cause the mine to sink in the water. Theattendant increase of pressure on diaphragm 14 and Bourdon 27 openscontact 24, de-energizing solenoid 32, and spring 59 closes valve 19.

When water pressure has increased to a predetermined value, Bourdon tube27 moves contact arm 26 into engagement with contact 25, contacts 35 and36 being bridged by contact member 34, a solenoid 37 is energized tomove armature 38, having head 39 in engagement with a diaphragm 41mounted in the wall of case 10 thus forcing the diaphragm 41 outwardlyof the casing 10 and increasing the volume thereof and causing the mineto rise.

When the mine has risen a short distance contact 25 is disengaged by 26through action of the Bourdon tube 27 ale-energizing solenoid 37.Armature 38 has a rack extension 42 which meshes with a pinion onratchet gear 43 engaged by a spring pressed pawl 44 of escapernentmechanism 45. The ratchet gear 43 and pawl 44 permit solenoid 37 whenenergized to quickly move diaphragm 41 outwardly, the ratchet overridingthe escapement 45 which may be of any well-known variety suitable forthe purpose. When solenoid 37 is de-energized ratchet gear 43 throughpawl 44 picks up escapement 45 which retards the inward movement of thediaphragm 41 a sufficient length of time to secure full effect of theincreased volume provide-d thereby and thus to more quickly bring themine to a state of equilibrium.

Interposed between solenoid 37 and ground is an electrolysis cell 46having a pair of spaced electrodes 47 and 48 mounted therein, aconductor 49 connecting electrode 47 to solenoid 37 and a conductor 51connecting electrode 48 to ground. A quantity of suitable electrolyte 52is contained in cell 46 and electrodes 47 and 48 are submerged therein.Electrolyte 52 is of a variety which generates a gas when subjected toelectrolysis. A gas vent 53 in cell 46 is controlled by a valve 54.

The purpose of the foregoing cell 46 is to prevent excessive use ofbattery 29 and to bring the mine into a more nearly perfect state ofequilibrium at the predetermined depth of submersion. When solenoid 38is energized, gas is generated in the electrolyte 52 and escapes slowlythrough valve 54, valve 54 being adjusted to permit the escape of gas ata limited rate less than the rate of formation of the gas thusincreasing the pressure in the cell. If solenoid 38 is energized forperiods of time greater than normal, larger quantities of gas aregenerated in cell 46, while valve 54 will permit only the escape of anormal amount of gas. Under such condition pressure within the cellrises sufi'iciently to force the electrolyte through electrolyte vent 55and through a check valve 56 mounted therein, thus venting a portion ofthe electrolyte into the surrounding water. Check valve 56 preventsentry of water into the electrolyte and permits venting of theelectrolyte into the water. Thus it will be seen that when theelectrolyte is vented the mine is lightened in weight and will rise.Lightening the mine will shorten oscillations thereof and solenoid 37will be energized for shorter periods of time. A portion of theelectrolyte will be vented on each subsequent oscillation until thequantity of gas generated is reduced to or below the normal amount.

Solenoid 32 is provided With an armature 57 which is connected to arm 58of valve 19, as shown in FIG. 2. When solenoid 32 is energized valve 19is opened. In order to return valve 19, a spring 59 is provided, thusvalve 19 remains open only while solenoid 32 is energized.

Referring to FIG. 3, the mine is launched and sinks to the bottom. Aftera time delay during which the bolts 12 are eaten away by electrolyteaction, the mine is released at point A of the diagram. Upon release ofthe mine from the anchor 13, switch 31 is closed. When the mine reachespoint B, switch arm 26 engages contact 24 energizing solenoids 32 and 33which respectively open valve 19 and bridge contacts 35 and 36. Withvalve 19 open fluid is forced, by pressure of the surrounding water ondiaphragm 14, through capillary tube 21 and into reservoir 17, as hasbeen heretofore described. As capillary tube 21 restricts flow of fluidout of chamber 15, mine 10 will probably come to rest at the surface ofthe water before diaphragm 14 has moved inwardly sufficiently to reducethe volume of the mine and cause the mine to sink.

During this downward motion of the mine at point C contact arm 26disengages contact point 24 de-energizing solenoids 32 and 33 and valve19 is moved to the closed position under action of spring 59. Bridgingmember 34 remains locked in engagement with contacts 35 and 36. Valve 19is closed thus preventing further inward movement of the diaphragm 14.

When mine 10 reaches point D during the descent thereof, con-tact arm 26moves under action of tube 27 to connect battery 29 with contact 25 thusclosing a circuit through contacts 35, 34, 36, solenoid 37, electrode47, electrolyte 52, electrode 48 to ground. Energization of solenoid 37moves armature 38 outwardly which moves diaphragm 41 to volumeincreasing position.

If the mine continues to sink by reason of excess weight, circuit forsolenoid 37 remains energized, building a supply of gas in cell 46 inexcess of the bleeding-off capacity of valve 54 thus producing pressurewithin the cell sufiicient to force a portion of the electrolyte throughcheck valve 56 and into the surrounding water as indicated at point E.This operation continues until the mine has risen to point P whereuponcon-tact arm 26 disengages contact 25 opening the circuit to releasearmature 38. Pressure of the surrounding water forces diaphragm 41inwardly against the retarding effect of escapement 45 thus prolongingthe lifting effect of the increased volume provided by the distendeddiaphragm 41.

The mine continues to rise reaching the secured point B whereupon valve19 is opened as aforedescribed to permit fluid to pass from chamber 15into reservoir 17 thus causing diaphragm 14 to move farther inwardly,reducing the volume of the mine.

The mine rises a less distance on the second upward trip than during thefirst upward trip, by reason of the trimming effect of the diaphragm 14.Each time the mine rises above the upper level or limit indicated bypoints B (FIG. 3) the diaphragm 14 is permitted to move farther inwardlythus further trimming the mine. In this way the upward travel of themine becomes progressively less during each succeeding oscillation byreason of reduction in volume of the mine by the inward portion ofdiaphragm 14 and the downward travel of the mine becomes less by thereduction in weight of the mine caused by the ejection or jettisoning ofthe electrolyle 52 at point B.

It is thus clear that when the mine is trimmed to approximately theweight of the water displaced thereby at the selected depth ofsubmergence, the oscillations will be infrequent and may be controlledentirely by the operation of diaphragm 41 at the mine passes points Dand F.

Obviously many modifications and variations are possible in the light ofthe above teachings. It is therefore to be understood that Within thescope of the appended claims the invention may be practiced otherwisethan as specifically described.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. Apparatus for equilibrating a subfloating mine comprising, incombination, a mine case, a volume increasing diaphragm mounted in thewall of said case, a volume reducing diaphragm mounted in the wall ofsaid case, pressure responsive means alternately connected to saidvolume increasing means and said volume decreasing means for activationthereof whereby the volume of said mine is increased or decreased tocause the mine to rise or sink selectively in the water, an anchor forsaid mine, electrolyte means for securing said anchor to said mine, saidsecuring means releasing by electrolysis said anchor from said mine apredetermined period of time after launching thereof, means engagingsaid anchor for preventing operation of said volume increasing means andsaid volume decreasing means until said'anchor is released.

2. Apparatus for equilibrating a subfloating mine comprising, incombination, means for reducing the volume of said mine, means forincreasing the volume of said mine, pressure responsive means forcontrolling said volume increasing and reducing means, an anchor forsaid mine, means responsive to the electrolytic action of sea water forinitially securing said anchor to said mine and for releasing saidanchor when said electrolytic action has continued a predeterminedlength of time, and means operative as said anchor is released forrendering said pressure responsive means operative to control saidvolume increasing and reducing means.

3. Apparatus for bringing a subfioating mine into a state of equilibriumcomprising, in combination, a casing, expansible means mounted in thewall of said casing for increasing the normal volume of said casing,compressible means mounted in the wall of said casing for decreasing thenormal volume of said casing, means responsive to pressure of thesurrounding water for controlling the operation of said expansible meansand said compressible means, a first solenoid for moving said expansiblemeans into expanded position, a second solenoid, circuit closing meansconnected to said pressure responsive means, said circuit closing meansbeing moved by said pressure responsive means to energize a circuit forsaid first solenoid for moving the expansible means at one end of themovement thereof and to energize said second solenoid for permittingmovement of the compressible means at the other end of the movementthereof, a cell containing a pair of electrodes submerged in anelectrolyte, said electrodes and electrolyte being a part of saidcircuit for the expansible means, a gas vent in said cell, anelectrolyte vent in said cell, an adjustable valve in said gas vent, acheck valve in said electrolyte vent for permitting venting of saidelectrolyte and for preventing entrance of seat water therein, saidvalve being adjusted to vent said gas at a rate less than that at whichit is generated by said cell whereby when an abnormal amount of gas isgenerated a portion of the electrolyte is vented into the surroundingwater through said check valve and said electrolyte vent.

4. Apparatus for bringing a subfloating mine into a state of equilibriumcomprising, in combination, a casing for said mine. a pair of flexiblediaphragms mounted in the wall of said casing, solenoid means for urgingone of said diaphragms outwardly of said casing to increase the volumethereof, a quantity of fluid chambered on one side of the other of saiddiaphragms, a reservoir for said fluid, restrictive means for reducingthe flow of said chambered fluid into said reservoir, a shut-oil valvefor said fluid, pressure responsive means for opening and closing saidshut-01f valve, said shut-off valve when open permitting the fluid toflow into said reservoir thus to permit the other of said diaphragms tomove inwardly under pressure of the surounding Water thereby to lowerthe volume of said casing, and switch means connected to said pressureresponsive means for energizing said solenoid means when the mine sinksbelow a predetermined level.

5. Apparatus for equiliberating a subfloating mine comprising, incombination, a mine case, a Volume increasing diaphragm mounted in thewall of said case, a volume reducing diaphragm mounted in the wall ofsaid case, a quantity of fluid retained by said volume reducingdiaphragm, a reservoir for receiving a portion of said fluid as thevolume reducing diaphragm is compressed by the pressure of thesurrounding water, normally closed shut-off valve means interposedbetween said reducing diaphragm and said reservoir, a solenoid foropening said valve means, a first circuit for energizing said solenoidfor said valve, a solenoid for moving said volume increasing diaphragminto volume increasing position, a second circuit for energizing saidsolenoid for said volume increasing diaphragm, a battery, a switchconnected to said battery for alternately energizing said first andsecond circuits, pressure responsive means for closing said switch toalternately energize said circuit, an electrolyte cell connected in saidsecond circuit and having a pair of electrodes immersed in theelectrolyte thereof, said electrodes generating in said electrolyte agas when said circuit is energized, an adjustable gas vent for said cellwhereby a normal amount of gas is released from said cell when saidfirst circuit is energized for a normal length of time and anelectrolyte vent for said cell having a check valve therein forpreventing venting of the electrolyte under normal operating conditionand for venting a portion of said electrolyte to lighten the weight ofthe mine when gas generated increases the pressure within the cell abovea predetermined amount.

6. Apparatus for bringing a subfioating mine to a state of substantialequilibrium comprising, in combination, a casing for said mine, a volumeincreasing diaphragm mounted in a wall of said mine, a solenoid formoving said volume increasing diaphragm to a volume increasing position,an energizing circuit for said volume increasing diaphragm, pressureresponsive means for opening said energizing circuit when the pressureof the surrounding water reaches a predetermined value as the mine risesand for closing the circuit when the pressure of the surrounding waterreaches a predetermined value as the mine sinks, a pair of electrodes insaid circuit, a quantity of electrolyte in which said electrodes areimmersed, a container for said electrolyte and said electrodes, saidelectrolyte generating a quantity of gas as current passes therethrough,means for venting said gas at a predetermined rate, and means forexhausting said electrolyte when said gas is generated for longer than apredetermined time.

7. A subfioating mine comprising a mine case, a first diaphragm in thewall of the case, said diaphragm being movable inwardly under pressureof the water to reduce the volume of the mine, a second diaphragm insaid case, said diaphragm being movable selectively in a direction toincrease or decrease the volume of the mine, means for retaining saidfirst diaphragm in a predetermined position, means for permittingmovement of said first diaphragm in a direction to reduce the volume ofthe mine when said mine rises to a predetermined depth, and means formoving said second diaphragm in a direction to increase the volume ofthe mine when the mine sinks to a predetermined lower depth than saidfirst prede termined depth.

8. A subfloating mine comprising a mine case, a first diaphragm in thewall of the case, said diaphragm being movable inwardly under pressureof the water to reduce the volume of the mine, a second diaphragm insaid case, said diaphragm being movable selectively in a direction toincrease or decrease the volume of the mine, means for retaining saidfirst diaphragm in a predetermined position, means for permittingmovement of said first diaphragm in a direction to reduce the volume ofthe mine when said mine rises to a predetermined depth, and means formoving said second diaphragm in a direction to increase the volume ofthe mine when the mine sinks to a predetermined lower depth than saidfirst predetermined depth and for retracting of said second diaphragm ata predetermined rate when said mine rises above said secondpredetermined depth.

References Cited by the Examiner UNITED STATES PATENTS 1,179,148 4/16Uhr et a1. 102-14 1,298,142 3/19 Wrightson l02l4 1,363,958 12/20 Dalen102l4 FOREIGN PATENTS 2,476 1912 Great Britain 10214 SAMUEL FEINBERG,Primary Examiner. SAMUEL BOYD, Examiner.

1. APPARATUS FOR EQUILIBRATING A SUBFLOATING MINE COMPRISING, INCOMBINATION, A MINE CASE, A VOLUME INCREASING DIAPHRAGM MOUNTED IN THEWALL OF SAID CASE, A VOLUME REDUCING DIAPHRAGM MOUNTED IN THE WALL OFSAID CASE, PRESSURE RESPONSIVE MEANS ALTERNATELY CONNECTED TO SAIDVOLUME INCREASING MEANS AND SAID VOLUME DECREASING MEANS FOR ACTIVATIONTHEREOF WHEREBY THE VOLUME OF SAID MINE IS INCREASED OR DECREASED TOCAUSE THE MINE TO RISE OR SINK SELECTIVELY IN THE WATER, AN ANCHOR FORSAID MINE, ELECTROLYTE MEANS FOR SECURING SAID ANCHOR TO SAID MINE, SAIDSECURING MEANS RELEASING BY ELECTROLYSIS SAID ANCHOR FROM SAID MINE APREDETERMINED PERIOD OF TIME AFTER LAUNCHING THEREOF, MEANS ENGAGINGSAID ANCHOR FOR PREVENTING OPERATION OF SAID VOLUME INCREASING MEANS ANDSAID VOLUME DECREASING MEANS UNTIL SAID ANCHOR IS RELEASED.